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Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by lisper on Thursday October 31, 2019 @02:10AM (#21406131)
How much money does society need to spend supporting the work you do before we can safely conclude that Einstein was actually correct and we don't need to test it any more?
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by ISL on Thursday October 31, 2019 @02:44AM (#21406242)
That's a great and important question. (doubly so for me, as constrained resources may see me leave the field, to which I have devoted my entire professional life, in the coming months) We are perennially grateful for the support we receive to do the work that we do.

To a high degree of approximation, Einstein's predictions are very, very correct. We are trying to look very carefully at Nature because we don't think we have the whole story.

It is possible that Einstein is exactly right. If so, we would never be able to describe the four forces of Nature with one unified theory. Today, we need two theories to describe everything we see -- the quantum-mechanical/particle-physics description of the Standard Model and gravity. There is no quantum-mechanical fuzziness in the mathematics of gravity, and there is no hint of the differential geometry of gravity in the mathematics of the Standard Model. The aspiration of almost every fundamental-physics physicist is to find a way to either simplify the Standard Model or connect it with gravity.

If the return on investment seems insufficent, know, too, that the technology we develop to push the boundaries of knowledge has important spin-offs. GPS is impossible without corrections from both special relativity and general relativity. The instrumentation we develop to make gravitational experiments possible on earth requires the development of new classes of seismometer [1] that may open new understanding of Earth's dynamics and allow better chip-fabrication instrumentation. The instrumentation developed to test gravity in space is also being used to measure the movement of mass (i.e. ice and water) on Earth's surface [2].

Even more important is the training we provide to students. Just as athletes train in the gym to get stronger, confrontation with the hardest known technical problems provides an efficient path for students and young faculty to become proficient at the entire range of modern measurement science. Alumni from our group have not only gone on to fancy academic positions, but also helped to redefine the kilogram, designed upgraded digital calipers used by tens of thousands of people worldwide, built key components of a major quantum-computing company's infrastructure, and more.

The people who work on these kinds of experiments are making a fraction of what they could make in industry. We are doing it for love, not money, and the returns to society are myriad.

[1] https://arxiv.org/abs/1707.03084 [2] https://gracefo.jpl.nasa.gov/

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by tomxor on Thursday October 31, 2019 @09:22AM (#21408397)
Good response. I think this is the clearest way to explain to people why researching X is important, the benefits to humanity are almost always in side effects of any research, development and engineering feats: The techniques, understanding and technology required to _attempt_ to figure out or achieve X are usually far more valuable than X itself and are often not known ahead of time, but can be invaluable to the future of humanity.

The problem is researchers are far more likely to express their interested in X to the public - quite right - since that must be their passion for the significant focus required to follow that path. This is what the public find so unintuitive, we need to focus on X to benefit from Y, although we don't know what Y is, but it has the potential to be far more useful than anything more direct.

Reminds me of the more literal explanation in a letter by Ernst Stuhlinger at NASA in response to a similar question:

https://www.forbes.com/sites/startswithabang/2017/10/26/even...

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by felixyz on Thursday October 31, 2019 @03:20AM (#21406388)
Really appreciate your tone and patience in sharing you experience here!
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by raattgift on Thursday October 31, 2019 @07:28AM (#21407574)
> constrained resources may see me leave the field

I am sorry to hear that - it will be a loss for Eöt-Wash.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by ISL on Thursday October 31, 2019 @09:13PM (#21415437)
I'm super bummed about it. It is a complicated story involving impedance mismatches between the goals of two administrative silos. The high-level goals are the same (good science, students, technology), but there are structural differences on how to get there...
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by salty_biscuits on Thursday October 31, 2019 @09:05AM (#21408250)
"GPS is impossible without corrections from both special relativity and general relativity"

I appreciate your comments in general, but I feel that this point needs to be tempered. Yes there are corrections due to SR and GR effects in GNSS, but they tend to get lost in the morass of the least squares residuals compared to all the other much bigger effects, like clock errors, orbital errors, ionosphere delays, etc, etc.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by ISL on Thursday October 31, 2019 @11:17AM (#21409710)
The relativistic corrections are cumulative (and, if I recall correctly, have opposite sign!). Without correcting for the shifts, it is my understanding that GPS would be degraded within minutes and useless in less than a day.

http://www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gps....

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5253894/

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by salty_biscuits on Thursday October 31, 2019 @05:01PM (#21413674)
You have to correct for the shifts, but no knowledge of relativity is required (maybe the SR correction is put in analytically but GR is definitely not). The least squares problem deals with it by lumping it with all the other time offsets for the pseudoranges for each satellite. And of these it is a small part of the error budget and is dealt with by averaging multiple measurements.
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by ISL on Thursday October 31, 2019 @05:43PM (#21414015)
The second reference cited above includes the passage:

"There is an interesting story about this frequency offset. At the time of launch of the NTS-2 satellite (23 June 1977), which contained the first Cesium atomic clock to be placed in orbit, it was recognized that orbiting clocks would require a relativistic correction, but there was uncertainty as to its magnitude as well as its sign. Indeed, there were some who doubted that relativistic effects were truths that would need to be incorporated [5]! A frequency synthesizer was built into the satellite clock system so that after launch, if in fact the rate of the clock in its final orbit was that predicted by general relativity, then the synthesizer could be turned on, bringing the clock to the coordinate rate necessary for operation. After the Cesium clock was turned on in NTS-2, it was operated for about 20 days to measure its clock rate before turning on the synthesizer [11]. The frequency measured during that interval was +442.5 parts in 10^12 compared to clocks on the ground, while general relativity predicted +446.5 parts in 10^12. The difference was well within the accuracy capabilities of the orbiting clock. This then gave about a 1% verification of the combined second-order Doppler and gravitational frequency shift effects for a clock at 4.2 earth radii."

It makes sense that offset corrections can be handled by a lumped model, as any relativistic corrections on timescales longer than an orbit will be constants of the satellite orbit. Making sub-orbit-duration corrections might require a model that captures more of the relevant physics.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by Jyaif on Thursday October 31, 2019 @11:31AM (#21409866)
Also, we surely would have compensated for relativity experimentally: "The clock seems to run 0.2% more slowly than predicted. We don't know why, but if we subtract 0.2% everything just work. Let's ship it!"
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by throwawaycanada on Thursday October 31, 2019 @02:44PM (#21412217)
Subtract 2% from what?
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by cs702 on Thursday October 31, 2019 @08:57AM (#21408187)
Short-termism, and the financialization of research, seems to be a huge problem in all fields of science.

By "financialization," I mean deciding which research projects get funding based on their expected measurable results, i.e., based on some rate of return that can be estimated today. If a research project can lead to more citations soon, or slightly better products soon, or lower costs soon, etc., it will get funding. Otherwise, it will not.

As a consequence, research projects with uncertain payoff but potentially transformational long-term benefits are... neglected.

:-(

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by short_sells_poo on Thursday October 31, 2019 @10:15AM (#21409029)
Your viewpoint is very agreeable, but how do you propose to do it otherwise? Given limited resources (which continues to be the case even today), you have to allocate them somehow. Can you think of a simple and objective measure to distribute the available resources between research projects?

It's all right to decry financialization of research, but it is a very difficult problem to solve.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by cs702 on Thursday October 31, 2019 @12:00PM (#21410176)
I would borrow from the "20% free for personal research" deal Google offers software developers: "spend 20% of your time on anything you want." Gmail, for example, was born as a 20%-spare-time project. (The creator of Gmail, Paul Buchheit, is now at Y Combinator.)

People who have dedicated their life to science should get more than 20%. Say, 50%: "Spend 50% of money/time/people on the funded project, 50% however you want."

I think my 50/50 idea would work quite well. Scientists still would have to demonstrate and justify the value of near-term projects to get funding, but would also get the resources they need to fund long-term projects with impossible-to-estimate present value.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by xtracto on Thursday October 31, 2019 @10:26AM (#21409143)
Round robin or following a uniform distribution?
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by zzzcarrot on Thursday October 31, 2019 @07:10AM (#21407488)
Stupid question but what is the two theories and why isn't gravity part of them?
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by coldtea on Thursday October 31, 2019 @07:13AM (#21407501)
"Today, we need two theories to describe everything we see -- the quantum-mechanical/particle-physics description of the Standard Model and gravity. There is no quantum-mechanical fuzziness in the mathematics of gravity, and there is no hint of the differential geometry of gravity in the mathematics of the Standard Model"
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by dr_dshiv on Thursday October 31, 2019 @03:20AM (#21406387)
Some argue that keeping talented people out of industry is a downside of the sciences not an upside.

Personally, particle physics irritates me because I don't believe in particles... It's all vibrations, man :)

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by TeMPOraL on Thursday October 31, 2019 @05:08AM (#21406880)
Academia isn't keeping talented people out of the industry. At any point, a talented person can leave the university, join a company, and easily quintuple their earnings.

It's the industry that's keeping talented people out by giving them mundane or bullshit jobs, and not leaving any space for long-term research and vision.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by raverbashing on Thursday October 31, 2019 @05:59AM (#21407117)
Though I might say that Academia is making a good job of keeping talented people out of it because their incentive structure is skewed.
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by xtracto on Thursday October 31, 2019 @10:28AM (#21409168)
This. I did not leave academia to search for fame and fortune. I left it because the bureaucracy and politics of it was terrible.
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by TeMPOraL on Thursday October 31, 2019 @06:34AM (#21407299)
That's true at the same time. It's a tough choice for those talented with love for science or a will to work on solving bigger problems.
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by coldtea on Thursday October 31, 2019 @07:14AM (#21407508)
>Some argue that keeping talented people out of industry is a downside of the sciences not an upside.

Yeah, instead of understanding the universe and core applications we could have more BS gadgets...

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by adrianN on Thursday October 31, 2019 @08:47AM (#21408124)
Think of the ads that could've been served!
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by yourapostasy on Thursday October 31, 2019 @08:07AM (#21407803)
I see it as the organizational abstraction of industry is an side-effect artifact of relative material scarcity, and a current, hopefully temporary condition in our species' evolution towards a future when advancing sciences becomes one of the major focal points of our endeavors, and the bulk of industry is largely automated away in the trail of a continuously-growing wavefront of advanced-and-advancing industry. Hopefully capitalism and industry will bootstrap us into that outcome, instead of mediocrely settling for a local maxima of extractive rentier structures. "Money is a sign of poverty", wrote Iain M. Banks, and I suspect the transition to that kind of wealth is an evolving continuum instead of an abrupt, sharp discontinuity.
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by nnq on Thursday October 31, 2019 @04:16AM (#21406666)
Hopefully a (theoretically) infinite amount (assuming infinite time) ...theories should continuously be re-tested, although it probably makes sense to spend an exponentially lower and lower amount of money on re-testing theories we know are true. But they should be re-tested, even if some experiments you'd only redo every 50 years or so!

For two important reasons:

1. as a species we must maintain technical capability to perform certain types of experiments - only way to 100% be sure we do this is by re-doing those experiments periodically

2. the fact that the "laws" of physics are fixed in any sense of the word, or that there even are such things as "laws of nature" is at its core a very very likely but UNPROVEN ASSUMPTION... we should always be open to the possibility that we live in a much stranger universe than we imagine and that the laws of physics themselves could vary and that we mush have capability to re-discover the new/changed laws, or to poke deeper at meta-laws

Also (2) is not as much lunacy as it sounds considering that the most likely (in the sense of "mathematically probable" considering the math of probability and information, not in "what we can determine experimentally with our primitive capabilities") setup from our universe models is more like we're in an N-th level "simulation" (a simulation in a simulation ... etc.) maybe running on a something like a "Boltzmann brain" in hell knows what soup of multiverses...

We may live insignificantly short lives and be practically meaningless on a grander scale, but if we dare the play the game of "guessing the laws of the universe" on a large scale, we shouldn't have the arrogance to assume that what we measure and deduce on an insignificantly small space-time volume in our ant-farm corner of the universe actually holds up directly through longer stretches of time and space!

Otherwise we're not really doing science, we're adherents to the religion called scientism, and we're not truly honestly rational, but merely praying in the church of rationalism! These are very very different things!

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by Erlich_Bachman on Thursday October 31, 2019 @07:21AM (#21407537)
Wouldn't we very quickly notice if any of the basic laws of phsyics would change, or if any of the physical constants would nudge even a fraction of a million - because our machines (like microchips, radios, like quantum computers, like satellites, GPS, etc. etc.) would stop working as they were intended?
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by mschuster91 on Thursday October 31, 2019 @09:16AM (#21408332)
Yeah, we would notice it, but that's not the point of re-running these kinds of experiments.

Just look what humanity was able to do in the Space Race with "computers" less powerful than an ordinary standard wristwatch of today: going to the moon, surviving there and coming back. Today? If it were not for SpaceX, the US would not have a path to access to its own manned transfer capability.

If we do not use abilities, we lose them. Knowledge gets forgotten, data bit-rots, machinery rusts apart.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by Erlich_Bachman on Thursday October 31, 2019 @10:06AM (#21408896)
> "computers" less powerful than an ordinary standard wristwatch of today: going to the moon, surviving there and coming back

This is more of a statement of how little computing power is needed for rudimentary space travel. The technology itself was quite advanced, just in other aspects than raw computing power.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by mschuster91 on Saturday November 02, 2019 @11:09AM (#21428084)
Sure but the US has lost so much abilities and especially knowledge. Most people active in the Moon-landing era are pensioners by now and there are at lwast two generations who have to start from scratch now instead of having decades of iterative tech improvements.
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by jeffdavis on Thursday October 31, 2019 @02:22AM (#21406168)
Assuming Einstein is correct is not the end, because we still have so many questions. For instance, why is Einstein correct?
Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by nabla9 on Thursday October 31, 2019 @04:49AM (#21406803)
It depends where you test.

General relativity should be tested and verified in energies and conditions where it has no been tested yet, because it's likely that there is crack there somewhere.

Many those military research projects mentioned in the article are pure crackpot science. They search where it easy to search and reasons to do so are usually based on misunderstandings of existing theory.

Re:Military Has Been Researching "Anti-Gravity" For Nearly 7... by hoseja on Thursday October 31, 2019 @03:51AM (#21406522)
Would be much better to spend that money on another VC funding round for WAaaS (Wiping Asses as a Service)!